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# Senior Software Engineer

- **Company:** Doghouse Recruitment
- **Location:** Germany
- **Experience:** Expert
- **Contract:** Permanent contract
- **Skills:** Java (Programming Language), Artificial Intelligence, Business Systems, Code Review, Data Integration, Software Debugging, Distributed Systems, Java Persistence API, Junit, PostgreSQL, Microsoft SQL Server, MongoDB, MySQL, Oracle (Applications), Software Tools, Mockito, Jetty, Multithreading, Load Balancing, Concurrency, Spring-boot, Technical Debt, Backend, Code Restructuring, Automation Anywhere, Microservices
- **Published:** September 6, 2026
- **Apply:** https://www.adzuna.de/details/5870289927

## About the Role

* 5+ years of backend Java development
 * Strong Core Java skills, including the ability to write Java without the Spring Boot framework
 * Genuine, hands-on experience using AI tools to refactor, clean up, or modernize legacy codebases (not just AI-assisted feature work)
 * Experience with concurrency and multithreading
 * Experience with JUnit, Mockito, or similar testing frameworks
 * Experience with PostgreSQL, Oracle, MySQL, SQL Server, or MongoDB
 * Comfortable working in a large, mature monolithic codebase, with curiosity about legacy decisions rather than a desire to rewrite from scratch

## Description

Senior Software Engineer - Core Java - Java 21 monolith - Remote within Germany

Our client is a data integration platform serving more than 2,000 customers, helping them connect business systems, automate workflows, and exchange data across cloud and on-premise environments. Their platform powers supply chains through real-time integration, automation, and intelligent data processing.

The codebase is a Java 21 monolith with no microservices and no Spring Boot but rather homegrown framework built on top of libraries such as Netty, Jetty, and JPA. This role sits in a team, where the focus is not distributed systems or load balancing but using AI to modernize and clean up legacy tech debt + improve internal AI workflows within the codebase.

What You'll Do

 * Design, develop, test, and maintain production-grade backend software in Java
 * Work through legacy code to identify and resolve tech debt, using AI-assisted engineering tools as a core part of the workflow
 * Contribute to technical design discussions and code reviews
 * Debug and optimize complex production systems
 * Collaborate closely with Product, QA, and fellow engineers to deliver high-quality releases
 * Take ownership of features from implementation through production


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